>> first of all, i wouldn't know how to produce 50 pounds of mdpv. i'm not a chemist. >> how had one of the silicon valley success stories gotten himself tangled up in all that? davis didn't know, but finally, he said, it was during a routine interview at mcafee's home he became convinced mcafee was a man unhinged. >> we were in his bungalow and he had a smith & wesson 38 special strapped to his chest in a holster. he takes the gun out. he opens the chamber. there are six bullets in. he drops them out and takes one of the bullets and he chambers it, closes it, spins the cylinder and he puts it to his head and i'm, like, john, we don't have to do this. and he says, i know we don't. your perception of reality may not be correct, and he starts pulling the trigger click, click, click, click, click, five times and there's only six chambers and then he pulls it a sixth time and nothing happens.